read_json.swift

#!/usr/bin/env xcrun swift

import Foundation

if NSFoundationVersionNumber < 1139.1 {
    println("You need Xcode6-DP5 and up to run this script")
    exit(1)
}

let args = Process.arguments
if args.count != 2 {
    println("Please specify *one* path argument.")
    exit(1)
}

let json_path = args[1]
var fm = NSFileManager.defaultManager()

if fm.fileExistsAtPath(json_path) {
    let data = NSData(contentsOfFile:json_path)
    var error:NSError?
    let json:AnyObject! = NSJSONSerialization.JSONObjectWithData(data, options:nil, error:&error)
    if let e = error {
        println("Error parsing JSON: \(e.localizedDescription)")
    }
    else {
        let dict = json as? NSDictionary
        if dict != nil {
            println("JSON is a dictionary:")
            println("\(dict)")
        }
        let arr = json as? NSArray
        if arr != nil {
            println("JSON is an array:")
            println("\(arr)")
        }
    }
}
else {
    println("File not found:\(json_path)")
}

竟然可以写 hashbang ！